Chair raising and lowering mechanism



y 12, 1966 HIDEHARU HORIE 3,260,051

CHAIR RAISING AND LOWERING MECHANISM Filed March 1'7, 1964 5Sheets-Sheet 1 INVENTOR. HIDE HA RU HOR/ E y 1966 HIDEHARU HORIE 3,

CHAIR RAISING AND LOWERING MECHANISM Filed March 17, 1964 5 Sheets-Sheet2 INVENTOR. H/DEHARU HORIE July 12, 1966 HIDEHARU HORIE CHAIR RAISINGAND LOWERING MECHANISM 3 Sheets-Sheet 5 Filed March 17, 1964 INVENTOR.HIDE/MAW HOE/E ATWZA/EX United States Patent 3,260,051 CHAIR RAISING ANDLOWERING MECHANISM Hideharu Horie, Osaka, Japan, assignor to TakaraCompany, New York, Inc., Brooklyn, N.Y., a corporation of New York FiledMar. 17, 1964, Ser. No. 352,624 6 Claims. (Cl. 6052) This inventionrelates to a hydraulic mechanism for raising and lowering a chair, forexample, a barber or beauty parlor chair.

An object of the present invention is to provide an improved hydraulicmechanism for raising and lowering a chair in a relatively simplefashion by the mere movement of a foot-operated pedal, and whereinrelatively short up and down movements of the pedal lifts the chair to araised position, and movement of the pedal to a lowermost positionreleases the chair from its raised position and lowers it to itslowermost position, and movement of the pedal to an uppermost postionlocks the chair against movement.

Another object is to provide a hydraulic mechanism of the type indicatedwith improved valve control means.

-A further object is to provide the indicated hydraulic mechanism withautomatic means for preventing further chair-raising movement after thechair has reached an uppermost position.

Another object is to provide a hydraulic operating mechanism for a chairwith improved hydraulic fluid sealing means.

Still another object is to generally provide a chair-raising andlowering mechanism of improved construction.

The above and other objects, [features and advantages of the inventionwill be more fully understood from the following description of theinvention considered in connection with the accompanying illustrativedrawings of an embodiment of the invention.

In the drawings:

FIG. 1 is a vertical sectional view of a hydraulic chair operatingmechanism in accordance with the present invention;

FIG. 2 is a vertical sectional view taken on line 22 of FIG. 1;

FIG. 3 is a vertical sectional view taken on line 3--3 of FIG. 1;

.FIG. 4 is a side elevational view of the upper part of the mechanism;and

FIG. 5 is a top plan view of the mechanism.

Referring now to the drawings in detail, the hydraulic chair operatingmechanism comprises a ram mounted for vertical up and down movement in ahousing 12 which has a head part -14 and a body part 16 provided withcylindrical bores 18 and 20, respectively, in which the ram slidablymoves. A hollow cylindrical housing part 22 is secured to the bottom ofbody part 16 and encloses the lower end of the ram. A cushion 24 issuitably mounted in the bottom of cylinder 22 for cushi oning the lowerend of the ram. The upper end of the ram projects from the upper end ofhead 14 and it is to be understood that the chair seat .25 which is tobe moved up and down by the ram is suitably secured to the projectingend of the ram, and the housing 12 is suitably secured at its lower endto an inverted discshaped base 26a.

Body part 16 of the housing is provided with a cylinder 26 in which aplunger 28 is slidably mounted for vertical up and down movement. Theplunger is normally biased by a helical compression spring 30 into anuppermost position as shown and for this purpose the upper part of theplunger is provided with an undercut part 3 2 which is engaged by theupper end of spring 30. The lower end of the spring rests .on seat 34provided in body part :16.

A plunger rod 36 is mounted for vertical up and down movement in acylinder 68 which is mounted in head part -14 of the housing and extendsdownwardly into recess or chamber 40 of body part 16. The chamberprovides a reservoir for hydraulic fluid. The upper part of the plungerrod extends from the top of head 14 and its upper end is provided withan L-shaped member 42. The cross-bar 44 of a U-shaped crank 46 rests onmember 42 and is operable to actuate rod 36 as will be more tfiu l lyunderstood hereinafter. The crank has a pair of laterally spaced arms 48(FIGS. 1 and 5) which are connected at one end thereof to crossbar 44.The opposite ends of the arms are each connected to a companion crankpin 50 which are in axial alignment with each other. Each of the crankpins extends into a straight inclined guide slot -52 provided in acompanion guide member 54. The guide members are laterally spaced fromeach other, as best seen in FIGS. 2 and 5, and are suitably secured tothe top of head '14 of the housing 12.

The crank pins are ope-rated by a pair of laterally spaced pedal arms 56and each arm is suitably connected to a companion crank pin. Afoot-operated pedal (not shown) interconnects the arms.

Ram 10 can be raised from the positions shown in FIGS. 1 and 2 by aseries of up-and-down movements of pedal arms 56. More particularly,downward movement of arms 56 causes crank arms 48 to rotate in acounterclockwise direction as viewed in FIG. 1, so that cross-bar 44 ofcrank 46 moves downwardly, causing plunger rod 36 to move down againstplunger 28. The plunger moves downwardly under the force of the plungerrod, compressing spring 30, and at the same time causing hydraulic fluidfrom chamber 58 to exert pressure on check valve 60 which opens thevalve to permit flow of hydraulic lflllld from chamber 58 to the annularspace 62 around the ram as well as to the lower end 64 of the ram, viapassage '66 in valve 60 and passage 68 in the lower part of body 16. Thepedal arms are moved downward ly a suflicient distance so that the lowerend 70 of plunger 28 is at the upper end 72 of an annular space 74 whichis formed between the lower part of cylinder 26 and the lower part ofthe plunger when the latter is in its lowermost position, for reasonswhich will be more clearly understood hereinafter. The amount ofdownward movement of the pedal for each raising movement of the ram isreadily determined by the operator after a short period of operatingexperience with the mechanism.

Upon release of the pedal after its downward movement, spring 30 returnsthe plunger 28 and plunger rod 36 as well as the pedal, pedal arms 56and crank 46 to the positions shown in FIGS. 1 and 2, and the mechanismis again in position for another downward movement of the pedal arms andanother upward movement of the ram. Of course the ram does not movedownward upon release of the pedal arms Ibecause valve 60 prevents anyback flow of hydraulic fluid from space 62 into chamber 58. Upwardmovement of the pedal arms results in the flow of .additional hydraulicfluid into chamber 58 from chamber 40 via passage 76 (FIG. 3) of checkvalve 78 to replenish the fluid which flowed into space 62 during theprevious downward movement of the pedal arms. The ram can be raised tovarious levels by additional down- Ward-and-releasing movements of thepedal arms.

In accordance with another feature of the invention, the ram can belocked in its raised position against movement by moving the pedal armsinto their uppermost position as shown by the broken lines in FIG. 4.For this purpose, a stop plate 80 is suitably secured by bolts 82 to thehead part 14 of the housing and is positioned in the path of upwardmovement of cross-bar 44 of crank 46. A split clamp 84 is secured to thetop of the head of the housing by a bolt 85 (FIG. and includes a splitlocking ring 86 which, in the unlocked position of the ram, looselyengages the ram and permits sliding movement of the ram relativethereto. The clamp includes a pair of laterally spaced arms 88a and 88bwhich, when arm 88b is squeezed toward arm 88a, causes closing of lockring 86 to thereby lock the ram in position.

Arm 88a is provided with a threaded hole 90 and arm 88b is provided witha clearance hole 92. An L-shaped handle 94 has a threaded portion 96which is screwed into threaded hole 90 and the handle extends throughclearance hole 92. The extending end of the handle is threaded andprovided with nuts 98 which are tightened against arm 88b of the clamp.It will be apparent that when the handle is rotated in acounterclockwise direction, as viewed in FIG. 4, arm 88b moves towardarm 88a and split ring 86 is tightened about the ram and locks it.

Handle 94 is operated by a link 101) which is pivotally connected at itsupper end to the handle at 102. The opposite and lower end of the linkis pivotally connected at 104 to the right end of crank 46, as viewed inFIG. 4.

As indicated above, to lock the ram in any position, the pedal arms 56are moved into their uppermost position. Upward movement of the pedalarms results in clockwise rotation of crank pins 50, as viewed in FIG.4, so that cross-bar 44 of crank 46 moves in an upward direction untilit engages stop 80. Continued upward movement of the pedal arms causesthe right ends of the crank arms 48 as viewed in FIG. 4, to movedownwardly and to the left, about the cross-bar 44 as a pivot, and thecrank pins 50 move downwardly and to the left in their companion guideslots 52 in guide members 54. It is to be noted that since guide slots52 are straight, cross-bar 44 is pulled slightly to the right, asillustrated by FIG. 4, but is restrained from any upward movement, andthe right ends of the crank arms move in unison with the crank pinssince they are secured to the pins. Downward movement of the crank pi-nsresults in the counterclockwise rotation of handle 94, as viewed in FIG.4, and arm 88b moves toward arm 88a to tighten clamp 84 and lock the ramin position. The upper stop and locking position of the pedal armsoccurs when the arms engage the top of head 14, at 105 in FIG. 4.

Lowering of the ram to its lowermost position is accomplished by movingthe pedal arms 56 to their lowermost position. This movement results inthe lowering of pin 106 (FIG. 1) of plunger 28 so that it engages theball of check valve 60 to open the valve and permit flow of hydraulicfluid from around the ram back to reservoir 40. The return-flow of thefluid is as follows: through passage 68 of body part 12, passage 66 ofvalve 60, by-pass chamber 74 which surrounds the lower part of thelowered plunger 28, passages 108, 110 and 112, respectively, in theplunger, and into reservoir 40.

Thus it can be seen that the structure for pumping, locking andunlocking, and lowering, comprising the crank 46, crank pins 50, andpedal arms 56 has no fixed axes with respect to the housing 12, and ineffect floats between the limits defined by the stop plate 86 and theguide slots 52. No part of this structure; 46, 50, 56; is pivotallymounted on or in fixed relation to any fixed part of the hydraulicmechanism. The force of the spring 30, acting through the plunger rod36, normally holds this structure; 46, 50, 5 6; in the position shown inFIG. 1, which position comprises a neutral position. When the pedal arms55 are moved upwardly from this neutral position to crossbar 44 of crank46 turns while at the same time moving to the right, as shown in FIG. 2,while crank pins 50 move linearly downwardly in the inclined guide slots52. Therefore, the motion of the crank arms 48 of crank 46 is not arotation, but is a compound linear translation.

In accordance with another feature of the invention, means is providedfor automatically preventing further upward movement of the ram after ithas reached its uppermost position even though the operator continues toactuate the pedal. This is accomplished by providing the L-shapedpassage 114 in the lower end of the ram. As a result, when the upper end116 of the passage moves above the upper surface 118 (FIG. 2) of bodypart 16, it is in communication with reservoir 40 and any additionalfluid which is pumped into space 62 by the action of the operatorresults in the displacement of an equal amount of fluid from space 62into the reservoir, whereby the ram remains in its uppermost position.

In accordance with still another feature of the invention, seal 120(FIG. 2) which prevents leakage of fluid from space 62 into reservoir 40is U-shaped and has a leg 122 which has one of its sides in slidingcontact with the ram, and its opposite side is slightly spaced from theadjacent wall 124 of body part 16. Accordingly, when the lower end ofthe ram moves above the seal, the latter is not damaged since hydraulicfluid is present on both sides of leg 122 to balance the pressure on theseal.

While I have shown and described the preferred embodiment of theinvention, it will be understood that the invention may be embodiedotherwise than as herein specifically illustrated or described, and thatcertain changes in the form and arrangement of parts and in the specificmanner of practicing the invention may be made without departing fromthe underlying idea or principles of this invention within the scope ofthe appended claims.

I claim:

1. Chair raising and lowering mechanism, comprising a movable ramadapted to be secured to the seat of a chair for raising and loweringsaid seat, and means for locking said ram in a position thereof, saidlocking means comprising clamping means movable from an inoperative ramnon-locking position to an operative ram locking position, and means foroperating said clamping means comprising a guide member having a guideslot therein, a pin movable in said guide slot from one positioncorresponding to said inoperative position of said clamping means toanother position corresponding to said locking position of said clampingmeans, means secured to said pin and having a part spaced therefrom toprovide a pivot for moving said pin from said one position to said otherposition, a member connected to said pin for rotating the latter, andstop means in the path of movement of said spaced part, for stopping themovement thereof during an initial movement of said pin operating memberin one direction so that continued movement of said pin operating memberin said direction causes said pin to pivot about said spaced part andmove from said one position thereof to said other position thereof foroperating said clamping means, pumping means including a plunger forraising and lowering the ram, including means controlled by operation ofsaid spaced part for controlling said plunger 2. Chair raising andlowering mechanism, comprising a movable ram adapted to be secured tothe seat of a chair for raising and lowering said seat, and means forlocking said ram in a position thereof, said locking means comprisingclamping means movable from an inoperative ram non-locking position toan operative ram locking position, said clamping means comprising asplit ring encircling said ram and a pair of laterally spaced armsextending from said ring and movable toward each other to clamp saidring on said ram in said operative ram locking position, and means foroperating said clamping means comprising a guide member having a guideslot therein, a pin movable in said guide slot from one positioncorresponding to said inoperative position of said clampingmeans toanother position corresponding to said locking position of said clampingmeans, means secured to said pin and having a part spaced therefrom toprovide a pivot for moving said pin from said one position to said otherposition, a member connected to said pin for rotating the latter, andstop means in the path of movement of said spaced part, for stopping themovement thereof during an initial movement of said pin operating memberin one direction so that continued movement of said pin operating memberin said direction causes said pin to pivot about said spaced part andmove from said one position thereof to said other position thereof foroperating said clamping means, pumpng means including a plunger forraising and lowering the ram, including means controlled by operation ofsaid spaced part for controlling said plunger.

3. Chair raising and lowering mechanism, comprising a movable ramadapted to be secured to the seat of a chair for raising and loweringsaid seat, and means for locking. said ram in a position thereof, saidlocking means comprising clamping means movable from an inoperative ramnon-locking position to an operative ram locking, position, saidclamping means comprising a split ring encircling said ram and a pair oflaterally spaced arms extending frm said ring and movable toward eachother to clamp said ring on said ram in said operative ram lockingposition, and means for operating said clamping means comprising a guidemember having a guide slot therein, a pin movable in said guide slotfrom one position corresponding to said inoperative position of saidclamping means to another position corresponding to said lockingposition of said clamping means, means interconnecting said arms andoperable to move said arms toward each other for said clampingoperation, a clamping means operating member connected to said armsinterconnecting means and said pin for operation of said clamping meansin response to movement of said pin, means secured to said pin andhaving a part spaced therefrom to provide a pivot for moving said pinfrom said one position to said other position, a member connected tosaid pin for rotating the latter, and stop means in the path of movementof said spaced part, for stopping the movement thereof during an initalmovement of said pin operating member in one direction so that continuedmovement of said pin operating member in said direction causes said pinto pivot about said spaced part and move from said one position thereofto said other position thereof for operating said clamping means,pumping means including a plunger for raising and lowering the ram,including means controlled by operation of said spaced part forcontrolling said plunger.

4. Chair raising and lowering mechanism comprising a movable ram adaptedto be secured to the seat of a chair for raising and lowering said seat,an operating member movable between upper and lower positions and in anintermediate range spaced from and between said upper and lowerpositions and means operable in response to movement of said operatingmember into said upper position thereof for locking said ram againstmovement, said ram locking means comprising clamping means movable froman inoperative ram non-locking position to an operative ram lockingposition, and means for operating said clamping means comprising a guidemember having a guide slot therein, a pin movable in said guide slotfrom one position corresponding to said inoperative position of saidclamping means to another position corresponding to said lockingposition of said clamping means, means secured to said pin and having apart spaced therefrom to provide a pivot for moving said pin from saidone position to said other position, said ram operating member beingconnected to said pin for rotating the latter, and stop means in thepath of movement of said spaced part, for stopping the movement thereofduring an initial movement of said ram operating member in one directionso that continued movement of said ram operating member in saiddirection causes said pin to pivot about said spaced part and move fromsaid one position thereof to said other position thereof for operatingsaid clamping means, pumping means including a plunger for raising andlowering the ram, including means controlled by operation of said spacedpart for controlling said plunger.

5. Chair raising and lowering mechanism comprising a movable ram adaptedto be secured to the seat of a chair for raising and lowering said seat,an operating member movable between upper and lower positions and in anintermediate range spaced from and between said upper and lowerpositions, and means operable in response to movement of said ramoperating member into said upper position thereof for locking said ramagainst movement, said ram locking means comprising clamping meansmovable from an inoperative ram non-locking position to an operative ramlocking position, said clamping means comprising a split ring encirclingsaid ram and a pair of laterally spaced arms extending from said ringand movable toward each other to clamp said ring on said ram in saidoperative ram locking position, and means for operating said clampingmeans comprising a guide member having a guide slot therein, a pairmovable in said guide slot from one position corresponding to saidinoperative position of said clamping means to another positioncorresponding to said locking position of said clamping means,, meansSecured to said pin and having a part spaced therefrom to provide apivot for moving said pin from said one position to said other position,said ramrotating member being connected to said pin for operating thelatter, and stop means in the path of movement of said spaced part, forstopping the movement thereof during an initial movement of said ramoperating member in one direction so that continued movement of said ramoperating member in said direction causes said pin to pivot about saidspaced part and move from said one position thereof to said otherposition thereof for operating said clamping means, pumping meansincluding a plunger for raising and lowering the ram, including meanscontrolled by operation of said spaced part for \controlling saidplunger.

6. Chair raising and lowering mechanism comprising a movable ram adaptedto be secured to the seat of a chair for raising and lowering said seat,an operating member movable between upper and lower positions and in anintermediate range spaced from and between said upper and lowerpositions, and means operable in response to movement of said ramoperating member into said upper position thereof for locking said ramagainst movement, said ram locking means comprising clamping meansmovable from an inoperative ram nonlocking position to an operative ramlocking position, said clamping means comprising a split ring encirclingsaid ram and a pair of laterally spaced arms extending from said ringand movable toward each other to clamp said ring on said ram in saidoperative ram locking position, and means for operating said clampingmeans comprising a guide member having a guide slot therein, a pinmovable in said guide slot from one position corresponding to saidinoperative position of said clamping means to another positioncorresponding to said locking position of said clamping means, meansinterconnecting said arms and operable to move said arms toward eachother for said clamping operation, a clamping means operating memberconnected to said arms interconnecting means and said pin for operationof said clamping means in response to movement of said pin, meanssecured to said pin and having a part spaced therefrom to provide apivot for moving said pin from said one position to said other position,said ram operating member being connected to said pin for rotating thelatter, and stop means in the path of movement of said spaced part, forstopping the movement thereof during an initial movement of said ramoperating member in one direction so that continued movement of said ramoperating member in said direction causes said pin to pivot about saidspaced part and move from said one position thereof to said otherposition thereof for operating said clamping means,

pumping means including a plunger for raising and lowering the ram,including means controlled by operation of said spaced part forcontrolling said plunger.

References Cited by the Examiner UNITED STATES PATENTS JULIUS E. WEST,Primary Examiner.

1. CHAIR RAISING AND LOWERING MECHANISM, COMPRISING A MOVABLE RAMADAPTED TO BE SECURED TO THE SEAT OF A CHAIR FOR RAISING AND LOWERINGSAID SEAT, AND MEANS FOR LOCKING SAID RAM IN A POSITION THEREOF, SAIDLOCKING MEANS COMPRISING CLAMPING MEANS MOVABLE FROM AN INOPERATIVE RAMNON-LOCKING POSITION TO AN OPERATIVE RAM LOCKING POSITION, AND MEANS FOROPERATING SAID CLAMPING MEANS COMPRISING A GUIDE MEMBER HAVING A GUIDESLOT THERIN, A PIN MOVABLE IN SAID GUIDE SLOT FROM ONE POSITIONCORRESPONDING TO SAID INOPERATIVE POSITION OF SAID CLAMPING MEANS TOANOTHER POSITION CORRESPONDING TO SAID LOCKING POSITION OF SAID CLAMPINGMEANS, MEANS SECURED TO SAID PIN AND HAVING A PART SPACED THEREFROM TOPROVIDE A PIVOT FOR MOVING SAID PIN FROM SAID ONE POSITION TO SAID OTHERPOSITION, A MEMBER CONNECTED TO SAID PIN FOR ROTATING THE LATTER, SAIDSTOP MEANS IN THE PATH OF MOVEMENT OF SAID SPACED PART, FOR STOPPING THEMOVEMENT THEREOF DURING AN INITIAL MOVEMENT OF SAID PIN OPERATING MEMBERIN ONE DIRECTION SO THAT CONTINUED MOVEMENT OF SAID PIN OPERATING MEMBERIN SAID DIRECTION CAUSES SAID PIN TO PIVOT ABOUT SAID SPACED PART ANDMOVE FROM SAID ONE POSITION THEREOF TO SAID OTHER POSITION THEREOF FOROPERATING SAID CLAMPING MEANS, PUMPING MEANS INCLUDING A PLUNGER FORRAISING AND LOWERING THE RAM, INCLUDING MEANS CONTROLLED BY OPERATION OFSAID SPACED PART FOR CONTROLLING SAID PLUNGER.